Logic devices such as a programmable logic device (PLD) or a field programmable gate array (FPGA) may be implemented on an integrated circuit (IC, or “chip”). The chip has a set of pins that are used to communicate, for example, data and control information to other chips. The logic device, upon power-on, may require to be configured by way of a “configuration image” that, conventionally, is stored in a flash memory that may be internal or external to the logic device.
In some known devices, for example, the logic device has a control block (CB) that receives a configuration image from the external flash memory chip, and uses the information in the configuration image to configure the logic device, when the logic device is powered on. Typically, some of the set of pins are assigned to the CB as mode select pins and others are used for communication between the external flash memory chip and the CB. For example, in some known devices, the CB samples the value of the mode select pins to determine the source of the configuration image. Moreover, the CB receives configuration data from the external flash memory via others of the set of pins.